Comment 38 for bug 1890772

I afraid we can not just trust (EDID_version >= 1.4 && EDID_supports_10bit). Because this issue caused by any problematic component in the middle of pipeline. To ensure the compatibility, better to just defautly set bpc=8.

Think of one scenario, a speaker get his Ubuntu machine onto stage, plug the HDMI or DP projector which works well on latest speaker who is using Windows machine. Then, he get dark screen or audio function lost....

I guess the Ubuntu user might not aware it's caused by bpc. The default behavior should offer better user experience.